We will study the convergence of two major public health problems in the United States today: cocaine and fatal injuries. Cocaine is now regarded as a plague responsible for many personal tragedies and serious disruption of our society. Fatal injuries are the leading cause of death for persons under 40 years of age. Cocaine may be a significant preventable cause of fatal injuries. The long-term objective of this study is to document the role of cocaine in injuries and to develop recommendations pertaining to health and law so as to prevent fatal injuries due to cocaine. The specific aims of this study include the assessment of the risk of homicide, suicide and accidents associated with cocaine use, how that risk is distributed among different age, sex and racial groups and how cocaine affects the circumstances of the homicide, suicide or accident. For the past decade we have worked with staff from the Office of the Chief Medical examiner of New York City and have unlimited access to the records of that office. This project will study all homicides (N=1600 per year), suicides (N=600 per year), accidents (N=1200 per year), and other injuries undetermined as to intent (N=700) from 1990 through 1994. Records include data on the demographic characteristics of victims, time, place and circumstances of the death, autopsy findings and routine toxicology assays for cocaine, alcohol and other drugs. Cocaine positive and negative deaths by each type of injury will be analyzed in an number of ways: through age-sex-race specific rates per population, through contingency tables for circumstances of the death (ex means of inflicting and type of injuries), through comparison of neighborhoods using United States Census data (ex. poverty, marital disruption) and through reports from relatives and friends at the time of identification of the body. For cases with short intervals of time between injury and death the presence of active cocaine versus inactive metabolites (ie withdrawal), will be analyzed for homicide, suicide, and drivers in fatal crashes using appropriate control groups.